Pulp grinder water control



March 22, 1960 D. VAWTER PULP GRINDER WATER CONTROL Filed April 16, 1957 INVE TOR. Mae/z IPULP GENDER WATER CONTROL Dale Vawter, Harrison Township, Calumet County, Wis.

Application April 16, 1957, Serial No. 653,136

2 (Zlaims. (Cl. 241-67) This invention relates to a grinder for use in the mechanical production of groundwood pulp. There are various types of such grinders to which the invention is adaptable. Groundwood or mechanical pulp is generally produced by taking short logs after they have been barked and cleaned and. pressing these logs sideways against a revolving natural or artificial grindstone, thereby reducing them to short fibers.

The principal objects of the present invention are to provide an improved grinder for use in the production of groundwood pulp from logs, which grinder may be operated at a high speed without causing serious burning or scorching of the wood fibers; to provide a grinder for use in the production of groundwood pulp, the grinder having improved means for feeding water to the grinding zone during the grinding operation; and, to provide a grinder of the type described which is efficient in operation and durable in use. Other objects and advantages or" the invention will become known by reference to the appended drawings and the following description of an apparatus embodying the invention.

In the drawings, which show a three pocket grinder equipped with the present invention,

Figure 1 is a side elevation of the grinder with parts of the outer casing shown cut away;

Figure 2 is an enlarged section taken along line 2--2 in Figure 1;

Figure 3 is a section taken along line 3-3 in Figure 2; and

Figure 4 is an enlarged view of a portion of Figure 2.

The grinder illustrated in the drawings includes an outer wheel-housing having a base It), vertical end walls 11 and 12 and an arcuate side wall 13. The grinding wheel 14 is mounted within the outer housing on a rotatable shaft 15 which extends through both end walls of the housing. Said shaft is jounaled in suitable endbearings 16 and 17, and is driven by a suitable motor (not shown).

The grinding wheel 14 is mounted on the shaft between a pair of collars or flanges 18 and 19. The collar 18 is internally threaded to fit threads 20 on the shaft 15. The other flange 19 is slidable on the shaft 15. A nut 21 fitting threads 22 on the shaft 15 serves to force the collar 19 against the side of the grinding wheel 14 so as to clamp the wheel between the two collars 18 and 19.

Logs are placed in three pockets, 23, 24 and 25, and are fed against the outer abrasive surface of the grinding wheel 14 by conventional pressure-applying means (not shown), and are ground to pulp by rotation of wheel 14 thereagainst. The ground pulp is discharged through an opening (not shown) in the bottom of the casing in the usual manner.

In accordance with my preferred embodiment as illustrated herein, water is supplied to the grinding areas or zones 26, 27 and 28 by means of radially extending hired tates Patent 2,929,568 Pa tented Mar. 22, 196i) ducts or conduits, generally designated 29, which ducts are preferably spaced longitudinally and circumferentially in the grinding face of the wheel 14. These ducts 29 are preferably arranged in circumferentially spaced groups, the ducts of each group being connected to a manifold 30 extending longitudinally in the wheel. An outer end of each longitudinal manifold 30 communicates with an inlet opening 31 extending through the collar 19.

These inlet openings are preferably uniformly spaced on a circle concentric with the axis of the grinding wheel 14, and as close as possible to the outer face of the stone so as to reduce the effect of centrifugal force.

As the grinding wheel rotates, water is supplied successively to the inlet openings by means of' an annular slipper or slip-ring 32, mounted within the housing in a position to register with and cover the inlet openings as the wheel 14 rotates.

As shown in Figs. 3 and 4, the annular slipper has a series of cavities or chests 33, each with an open mouth 34 from which water may flow into each of the inlet openings 31 with which each cavity 33 may be in register at any given time. Water under pressure is supplied to each of the chests 33 through a water feed opening 35, as shown in Fig. 3, to which afiexible hose 36, as shown in Fig. 2, is connected.

As illustrated in Fig. 3 of the drawings, each chest 33 supplies water for only one of the three grinding areas.

it will be seen that for each complete revolution of the shaft 15 (which rotates the wheel) there will be a complete revolution of each of the outlet ports 29, so that each of the ports 2& will be in register with a grinding zone, e.g., zone 27, during a definite fractional pe riod of a single revolution of the wheel 14. Similarly, one or more of the inlet ports 31, during a fractional period of the revolution of the wheel 14, will be in register with a chest or cavity 33. Thus, by setting the cavity in the proper angular position relative to the grinding zone 27, the flow of water from the chest 33 and through the ports 31 into the wheel 14 will be synchronized with the flow of water from the wheel out through the ports 29 into the grinding zone 27. Thus, each of the ports 29 will deliver water to the grinding zone during a period which is only a fraction of a whole revolution of the wheel 14.

The slip-ring 32 is pressed against the side wall of the collar 19 by means of a series of coiled wire compression springs 37 interposed between the slipper 32 and the casing 12. Each of these springs surrounds a stud 38 on the inner end of which the slipper is slidably mounted. The outer threaded end 39 of the stud 38 is reduced in diameter and extends through the wall 12 of the housing; it is locked in place by a washer 4i) and a nut 41.

The grinding wheel 14 illustrated in the drawings may have a diameter of 60 inches and can be rotated at about 250 r.p.m. Except as herein described, it may be of conventional design.

As the grindstone rotates, it may be desirable for various reasons to expel water mainly from that portion of the grinding face which is then passing through a grinding area rather than from that portion of the face which is outside of the grinding area. Accordingl it may be desirable to adjust the position of the slip-ring 32 circumferentially of the wheel to compensate for the time lapse in the passage of the water from the chests 33 to the outer face of the grinding wheel.

To advance or delay the flow of water into the rotating inlet openings, the studs 38 extend through arcuate slots 42, as shown in Figure l, which are concentric with the wheel axis, so that when the nuts 41 are all loosened, the slipper 32 may be moved circumferentially to a new position and, then locked in the new position by tightening said nuts a Such modifications in the apparatus of the present inventionas are-Within the skill of those versed in the art are contemplated. as being within the scope of the'present invention.

Various features of the present invention which are believed to beenew' are set forth in the accompanying claims. a,

abrasive material and provided-with pocket space for wood to be ground on said outer-surface, and with a continuous series of conduits spaced circurnierentially around the-periphery of the wheel and extending outwardly through said outer surface of the wheel, means for rotatingsaid wheel, means for forcing said wood against said outer surface, and means synchronized and cooperating with the wheel rotating means for forcing Water outwardly through the respective-conduits during a-period of less than a whole revolution of the wheel, whereby during said period water is discharged into said pocket space only from thoseconduits which are in register with the pocket space.

2, In a grinder for use in making groundwood pulp, the combination of a wheel having an outer surface of abrasive material and pr'ovidedwith a plurality of conduits extending inwardly from said outer surface of the Wheel, said conduits being arranged in circumferentially spaced groups which are longitudinally spaced along said outer surface of said wheel, said groups of conduits having circumferentially spaced inlet openings on a side of said wheel, means for forcing wood against said outer surface in an arcuate zone of contact between the wood and the wheel, a relatively stationary slipper pressing against a' side of said wheel and formed with a cavity having a mouth adapted to register with said inlet openings successively as the wheel rotates, and means for feeding water into said cavity, whereby, as the, wheel rotates, water is delivered into said zone successively from the spaced groups of conduits.

References Cited in the file of this patent UNITED STATES PATENTS 351,285 Ritchie Oct-l9, 1886 983,055 Hosmann 2.. Jan. 31, 1911 2,050,749 De Mers Aug. 11, 1936 2,282,887 Roberts May 12, 1942 2,378,070 Eastwood, June 12, 1945 2,560,972 Martin July 17,1951 2,769,286 Beth ,Nov. 6, 1956 FOREIGN PATENTS 151,221 Germany Mar. 22, 1903 834,518 Germany Mar. 20, 1952 

